PARENT SESSION
Poster Session # 19: Insect and Invertebrate Ecology.

Thursday, August 7 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.

Temperature effects on life-history characteristics of the Giant Waterbug, Belostoma lutarium (Hemiptera: Belostomatidae).

Swart, Charles^*,1, Felgenhauer, Bruce¹, Jaeger, Robert¹, ¹ Department of Biology, University of Louisiana at Lafayette, Lafayette, LA, 70504

ABSTRACT- Thermal energy is known to cause variation in reaction rates of most biological processes. Environmental temperature can have drastic effects on life history characteristics including growth rates, body size, fecundity, and propagule size. In most species, body size can affect clutch size through limitation of egg production or egg care by the female. In animals with paternal care, male body size can also limit clutch size. Males of the semi-aquatic heteropteran, Belostomatinae brood eggs on their dorsal surface, thereby limiting clutch size by the area available due to body size. Males can also affect body size of the offspring by preferentially occupying warm or cool microhabitats during brooding and egg hatching. Our results indicate that temperature has a significant effect on adult size, time to maturity, and egg size, but not growth rate, in the Giant Waterbug, Belostoma lutarium. Furthermore we use data from field measurements and field collected and laboratory reared animals to develop a model predicting seasonal fitness based on body size, temperature, and time to maturity.

Key words: temperature effects, body size, growth rate